Apparatus useful in directional well drilling



Aug. 24, 1943. A. L. ARMENTROUT APPARATUS USEFUL IN DIRECTIONAL WELL DRILLING Filed April 4, 1941 2 Sheets-Sheet l fl r/y mflfzarlgy 1943- A. ARMENTROUT I 2,327,693 APPARATUS USEFUL IN DIRECTIONAL WELL DRILLING Filed April 4, 1941 2 Sheets-Shet 2 Patented Aug. 24, 1943 new APPARATUS USEFUL IN DIREOTION ADZWELL DRILLINGJ.

Arthur L; Armentrout, Los Angels, Califg'. Application April 4, 1941; Serial No.- 386;851}

a claims; (01. 2554-15) This invention pertains to well drilling equipment and relates more particularly to apparatus useful in directional Well "drilling operations.

In the=drilling or deep wells,-such as oil wellsand gas wells; it is sometimes necessary to resort 5,

to' whatare knownas directional drilling opera-- tions. Thus; it may be desired to direct the drillingtools'toward-a given earth formation or it may be-necessary'tc change the' direction of the drilling tools to straighten the well or to return th'e tools to-the intended course: I will" herein refer to-such operations as directional drilling, itbeing understood that this term is-to be construed broadly to cover any andall well drilling operations wh'ere the wellibore is to be given a pre-determinedi or undetermined='directio'n difierent from its initial direction or is tobe returnedto its intendedcourse at its lower end or at any other point.

Tools and methods of various kindshavebeen proposed and employedfon carrying-on direc tionakdrilling operations." So far as I am aware the-.drillingtools employed in such'oigierations:- have tbeenzrotated :andzfed. into the earth formatlOIl' to formuthe side track bore: or directional bore. The: side; tracking bit or drilling. toolzis usually deflected byz'awhip. stockbutother defiecting'means' have been employed. Thedeflection of;the:r0tating;dri1ling tool by any means; whatsoever resultsin bending of therotary well drillingstringl; The bending-oftthe drilling string causes :the. drilling tool to;.wh ip and gyrate as it; rotates so. that itoftentakes a course quite dif ferent from that intended and there is no assurance. thatxthe 1 drilling :tool will proceed in the desired. direction. For-this reason directional. welldrillingoperations are often unsuccessful; There'aremany other cliificulties encountered in directional well drilling-as now practiced and the directional drillin operation are usually prolonged and expensive.

A general iobject vof'this invention isto providev a simple, dependable directional well drilling. methodranda highly effective apparatus for car rying out'themethodz i 3 Another-object of the invention is to provide a practical method for :the directional drilling of wells by means ofiwhich' the drilling tool may bev made to drilla side track boreor directional bore in'any selected direction and at any selected reasonable angle relative to the initial direction of the well bore.

Another object ofthis invention is to provide a method useful in :the directional drilling. of wells. that avoids rotation ofEthe'idrilling.toolemployed to-form the side tracl bore-or directional bore= and; therefore; ob'viates-= thediificulties and un certainties encountered in the operation of prior: directionaldrilling' toolst Anotherob'j ect of "this invention is .to .providea a method of the character referred to in.which:-

. the bit or drilling tool mayr be.very':accurately oriented before starting-.1: the; drilling;3o.peration and in which the directioniofi the tool i-isiamain'eztained throughoutlzthe drilling; ofg'theaside track:

bore. Y

Anothennbjeetz; 0i! thiseinventiorra is;- to-zprovidei. aurnethodpiofithe characterzreferred tmWhich'may: bequickly periormediandiwhichimam be carried;

' out withoutrinstalhngawliipt'stocks or otherequimmentthat'zmight obstruct; the well; or interfere with subsequent: drilling-:operations: i

AIlOthBI'E objector: this-invention is; to. provide; directional well drilling-l equipment; by. means-of; which; thezbi-t;-or.;dril1ingitool may be accurately; oriented and given the desired angle of operation; withoutemployinggaq whip stock, or other expensive devicerliable ito iail or-rbecome; displaced.

Another ,1 object of this invention 1 is,-;to :provide; directional well drilling equipment embodying a: percussive typebit :and: eiiiective:- means-g for: operating the bit' to drill thes.-sideztrack-. here: on directionaliboree V The :v-arious-cbjectsa and: features-mi: my invenetion' will ;,be fully runderstoodsfrom the ziollowing; detailed. description of z typical,- preferred. f OImS; of the. apparatus and a. typical manner of carry:- in lzoutytheimetholdnoi the-invention; throughout: which descriptionreference ismade to the ac-p companyingdrawings; in whichze Fig, 1 is a longitudinal .lsectional view of' the! lower; portion of: a well here: showing theap;- para-tus; of; then. invention. in i an initial. position and. 1 illustrating; the surveying; device; extended from; the bit forvoperatiom. Eiggz is) a view: similar to "Fig-. l; show-ing the: directional 1 drilling; tool; or bittin. operation -intherdirectionalrborea Fig. 3i-is an enlarged: longitudinal detailed secs: tional view-of the impact:.generating mechanism with-:the partsiinzthe;normalypositionsi, Eig. l is an enlarged; fragmentary, longitudinal.- sectional viewiofithe upper portion. of time impact generatora showing thewfioating;plungen-orfollower; Fig; .5;- is an; enlarged fragmentary?longitudinal; detailedsectional .--view: ofthe. intermediate :portion of g the; impact generator illustrating the hammer; and its: control -1 means. Figs. 6 and. 7. are enlarged trans-verse detailed; sectional iviewsa-rtaken :as in? dicatedrbyflines iii-61 andu Ir-'1 respectively,- on. Fig. 3 Fig t; .is a: fragmentaryrlongitudinalidea is not to be construed as limiting orrestricting the invention to the particular features set forth. I will first proceed with a detailed description of the apparatus and will then describe the method.

track bore or directional bore D as will be later described. In the preferred form of the invention the impact generator I is actuated by reciprocation or longitudinal movement of the operating string S. The impact generator I0 is connected between the curved or angular section II and the bit I2, having one end connected with the lower end of the section II and having its other end connected with the upper end of v the bit I2.

The impact generator I0 is a telescopically assembled structure including an outer tubular 'member or body I4 and a mandrel I5 entering the body I4. In the arrangement illustrated the outer member or body I4 is attached to the curved or angular section II of the operating string S and the mandrel I5 carries the bit I2.

The apparatus of the invention as illustrated f in Figs. 1 to 8, inclusive, may be said to comprise, generally, a drilling string or operating string S having a curved or angular section I I, a percussive type drilling mechanism or impact generator ID on the section II, a directional drilling bit I2, and means I3 for orienting the bit I2 in the well preparatory to operation of the impact generator I0.

The operating string S serves to carry the several drilling elements and is tubular to conduct drilling fluid andsto receive or pass elements of the orienting means I3. Thestring S is a tu-' bular well string of tubing or drill pipe made up of sections or stands in accordance with the common practice. It is preferred to employ a string S which is considerably smaller in diameter than the Well bore B so that the string or a lower por- 0 tion of the string may assume a position at one side of the Well as shown in Figs. 1 and 2. The string S formed of conventional tubing, drill pipe, or the like, is flexible to a substantial de'-. gree as will be appreciated by those skilled in the art.

' The section I I serves to carry'the'impact generator I0 and drilling bit I2 and is such that the bit I2 is offset from, out of alignment with, or at an angle to the longitudinal axis of thestring S. The section II may be a length or section of drill pipe, well tubing, or the like, and is connected with the lower end of the string S by a suitable coupling or collar II. In accordance with the invention the section II is bent, curved or made angular. It is preferred to give the section II its desired shape, curvature or angularity before introducing the equipment into the well bore'Band the section 'I I 1's sufficiently rigid to resist distortion and substantially maintains its shape when the tool is in operation. As illustrated in the drawings the section I I may have a substantial curvature or angularity, with its upper part aligned with the string S and with its lower part extending downwardly and laterally ata substantial angle of the string. The curvature or angularity of the section II is such that the bit I2 is at one side of the bore B while the string S lies at the opposite side of the bore.

The angularity of the section II is not so great that the equipment cannot be easily run intoand out of the well. In accordance with the present invention the section II maybe given any selected or required curvature or angularity to adapt the apparatus for-use in any particular job and for any given purpose.

The percussive mechanism or impact generator I0 is operable by manipulation of the string S to impart downward impacts or blows to the section I I to cause the bit I2 to drill the side- A tubular sub "I6 is attachedto the lower end of the section II and a tubular part, which I willterm a barrel I8, is connected between the sub l6 and the body It. Thesub Ifi has-a pin lfl threaded in the upper end of the barrel v I8, and the lower end of the barrelisthreaded in the upper part of-the body I4. As shown in Figs. '3 and 4 the lower end of the barrel I8 forms a downwardly'facing annularshoulder 2 0 -in the. tubular outer assembly of theimpact generator ID. A tubular shoe 2| is provided: on the lower.

end of the body It The shoezl may have a reduced upper portion threaded in the lower end; of thesbody I4 and arranged and proportioned so that its upper end forms anupwardly facing annular shoulder 22 in the tubular body assembly.

The tubular outer assembly'M, I8 and 2|, just described, maybe larger indiameter than the. operating string S but is preferably much smaller in diameter. than the well bore Bto be received in the wellwith substantial clearance asshown inFigs.1and2. The mandrel I5 of the impact generator III slidably passes through the shoe 2| to project down-- wardly for connection with the bit, I2. An annular upwardlyfacing shoulder 23 is provided in the shoe 2I and the mandrel I5 hasanexternal annular flange 24 whose lower;end is adapted to cooperate with the shoulderz'23 to limit relative longitudinal'movemen't between the mandrel I5and The portionof the-mandrel I5. above the flange 24 is' reducedin external 'diameter to leave an annular chamber in the body:

I 4 and shoe M. 'A hardened annular or tubular the body It.

anvil 25rests on the. flange 24 oris: secured to the mandrel I5 to bear on the flange. The outer tubular assembly I 4, I8 andJZI and the'mandrel I5 are keyed or. clutched together for .the transmission of rotation orturning forces when they. are fully extended. In the particular, case H1115? trated the mandrel flange 24 and the body shoul-.

der 23 have engageable. clutch parts 26 for. the

transmission of rotation.

The impact generator Illiurther includes a;

hammer means. operable by reciprocation of the string S to impartdow'nward hammer blows 0r impacts to the anvil 25. .This'means includes. I

an elongate tubular part of substantial weight which I will term the. hammer 21. The hammer 21 is 'shiftable or slidable longitudinally. in the body It. In the'zlpreferredconstruction,theupper and lower ends of the hammer 24 have notched or grooved peripheral flanges 28; for

guiding the hammer in the body I! while allowing free flow of fluid past or aroundthehammer during relative movement betweenthe body and hammer- The tubular hammer21 .shiftablyj or slidably engages on thereducedupper partofrthe mandrel l5. Aireplaceablethardened hammeri head 29 is provided on thelower'end of the hammer 2'! for strikingthe anvil 25. Iihavesh'own the replaceable headu29: threaded-andlocked in the lower portion of the hammer 21 and-formed to have the lower notchedguide flange 28 of the hammer. I i 1 The hammer means or impactiigenerator I- further includes a mandrel or stem secured in the outer body assembly I4;- l8 and 21 and arranged to pass through orinto thehammer Z I'JW-In the preferred construction this stem is sectional comprising. an upper section anda lowersectionai. The. upper section wUisfiXed to thesub I 6 and extends downwardly .in' the barrel 1 I 8.- with substantial clearance to leave, anannular. chamber therein. The upper end of. the section; tilmay be fixed to the pin .I9of the sub.:l6.- The lower section 3|.is provided. with an enlarged head 32 threaded on the loweri'portionofxthe sectiont ll and formed to leave. or provide-arr 'annular downwardly facing shoulder'33 onthe stem- The shoulde'r;.33 lies inthe same horizontal or. transverse plane as the :shoulder ziiliand has grooves or notches S te to permit a free icirculae tion of fluid passed .or aroundthe head 32 when1 the impact generator ill. is in operation;

The lower Portion: of thestemsection at .is reduced in external diameter to leave or provide. a.v downwardly facing. annular shoulder '35. {The shoulder 3G is spaced ,a considerable. distance. be loW'the head 32 and, is taperedor sloped down-. wardly and inwardly. The stem sections 35 and 31 are tubular to conduct fluid from the sub Iii to the tubular mandrel I E5. of the mandrel has an enlarged central bore or opening 35 which receives the reduced lower por-,;. tion of the stemsection 3].: Packing 35 is provided on the stem section ill to slidably seal with the wall of the opening 35. A gland 31' is threaded on the stem section 3I to support and com-v press the packing 3t. p r u The hammer 2'! is spring actuated orspring loaded and is controlled by an automaticlatch means to be suddenly and forcibly drivenagainst the anvil 25 during each downv stroke, of; the. string Sand body I i. A coiled springp38 is arranged in the body MLunder compression b,etween the upper end of the hammer 21, and the shoulders 28 and 33, The spring 38 tends to drive or move the hammer 21 downwardly relative. to the body M and mandrel I5. Itis preferred to construct and proportion the spring 33 so that there may be a free flow of fluid throughor, around it and the notches 34- at the shoulder33. provide for a free fluid movement through or passed the upper end of the spring I The latch means for controlling the hammer 2? includes a semi-annular or partially annular latch block 39' slidably riding in a correspond inglyshaped transverse'slot 48 in the Wallof the hammer 27. The block 3 9 has flat upper and lower sides shiftably engaging in the slot 40 andthe lowerside of the block is adapted to engage the upper endof the mandrel [5 to releasably hold the hammer 2'! against downward movement with respect to the mandrel. The block 39 is provided with a downwardly and inwardly sloping inner surface All engageable by the shoulder 34 as will be later described. The outer surface of the block 39 may slope downwardly and outwardly. The block 391s spring urged or spring held being. urged inwardlyby a leaf-spring 42a;

The leaf springAZ maybe attached to areduced portion of the hammer} 21 by a-ibolt-or screwi li;

The upper portion a hammer 21. and the. hammer is suddenly driven;

downwardly by the compressed'spring 38f andi its head 29 forcibly. 'strikesithe. anvil 25. When; the body 114 is moving downwardlyas just de.-.- scribed, and before thejrelease. of the latchblocki 39; the shoulder ZZi passes down-ward belovrthei= W anvil top 25. on thefollowing'return StI'OkGiOI;

.,the upwardly moving body M. The body I41 moves upwardly until the block3. reaches;the

upper end of the mandrel I5 at which time the spring 42 moves the block inwardlyto it's latchede postion illustrated in Figs. 3 and 5; At this time the shoulder 23ireaches or 'approaches the flange 1 2.4.and the parts are in the positions,willustratedc in Figs. 3 to '7, inclusive.

It is' preferred toprovide. means for assisting the return movement of the body M relative. to:

1 the mandrel I5 and .to absorb "shock which may result fromsudd'en downward movement of the body with respect to the mandrel-.1 helicali spring or coiled. spring; 44 is: arranged under: compression between the lower end of thestem. section 3i and, therbottorn of the opening 35: The. spring M is lighter; or weaker than" the spring'38."

Itis preferred tomaintain a bath of oil or other suitable liquid in the body It 'to lubricate the various parts and to exclude the drilling sembly. A floating annular'plunger or follower.

46 is provided in the annular chamber within the barrel I8 atthe upper end of the column of oil: orqother liquid contained in the tool. A.plurality of spacedlateral ports 4'! is provided in the wall of the stem section 30- above, the follower 46 tomaintain the upperportion of the barrel-Iii in communication with the string S so that the: upper side of the follower 46 is subjected to .the pressures existent in the string S and .well bore. -With this arrangement the oil or fluid contained L in the body' I4, shoe 2 i and the lower portion of g the barrel I8 is held under substantially the same I pressures as the fluid inthe string S and the WGHSO that there: is little tendency for fluid'td leak into or out of the hollow sealed assembly.

The floating follower 46 maybe of any se lected construction. -As illustrated in Fig. 3 of the drawings the follower 46 may be made up ofa-plurality of spaced rings 48- with upwardly and; downwardly facing chevron :packing $9 ardesign, construction, etc.

ranged between the opposing ends of the rings' 48; The assembly of the rings 48 and packing 49 is held together in the correct operating rela tion by spaced screws or bolts 50. When the mechanism or impact generator I is operated the follower 46 is free to ride up and down as the volume of the chamber in the tool, etc. increases anddecreases; The floating follower 46 completely separates the contained oil, or the like, from the well fluids and prevents contamination of the oil or contained fluid.

The directional drilling bit I2'is secured to the lower end of the impact generator Ill. In the drawings I have shown the bit I2 connected with the mandrel I by a suitable collar or connec tion 52. The bit I2 may be varied greatly in ably of a type which operates eifectivelyby a hammer action or percussive action. In the construction illustrated the bit I2 is an elongated thick walled tubular member having an enlarged head at its lower end which presents a multiplicity of downwardly directed teeth 53. There may be an annular series of teeth 53 surrounding the lower end of the opening 54 in the bit. The teeth 53 are adapted to form an annular or cylindrical bore in the earth formation having a diameter smaller than the main well bore B but sufficiently large to receive the directional drilling equipment with clearance so that well fluids may be circulated through the directional bore D if desired.

Fig. 9, illustrated another form of bit that may be used'with the apparatus. The bit IZ shown in Fig. 9 is secured to the lower end of the mandrel I5 by the connecting member or sub 52 in the same way as the bit I2. The bit I2 is a generally cylindrical member provided with a sloping or pitched lower end 55 formed or designed to cut into the earth formation. The bit I2 is a spudding bit and is effective in starting a new bore or a directional bore D. It is to be understood that the bit I2 is tubular or provided with a central vertical opening similar to the opening 54 of the bit I2,

The orienting means I3 is such that the position of the bit I2 or I2 may be accurately determined prior to initiating the directional drilling operations so that the bit may be re-positioned if this is found necessary. The orienting means I3 includes a locating seat or orienting seat 56 at the bit I2 or. I2. In the particular case illustrated the seat 56 is formed in the sub 52 and is in the nature of an upwardly facing annular surface on the interior of the sub. The seat 56 is sloped or pitched at a substantial angle and the rotative position of the angular plane of the seat 56 is known. In other words, the seat 56 bears a given rotative position with respect to the bit I2 or I2, the mechanism Ill and the string S. The opening through the sub 52 is enlarged above the seat 56 to constitute a cylindrical socket 51,

The orienting means I3 further includes a de: vice' or object to be dropped or lowered through the string S to cooperate with the seat 56. This object will be termed a go-devil 58. The go-devil 58 may be run into and out of the string S on a cable or line L. The go-devil 58 is generally The bit I2 is prefer sloped or pitched toconform to the seat. The

seat 56 and face 60 are suchthat the go-devil 58 automatically turns when the face comes into.

of the instrument. As surveying instruments of.

the single, shot type are well known to those skilled in the art the details of the instrument have been omitted from this disclosure. As illus-v trated in the drawings the surveying instrument 6| is an elongate tubular member secured to the go-devil 58 to extend downwardly therefrom. The instrument 6I through the sub 52 and the opening 54 of the bit with suitable clearance and is designed so that its sensitive magnetic means or compass means is housed in that portion of the instrument which protrudes below the bit I2 or I2 As illustrated in Figs. land 9 of the drawings the instrument 6I projects a substantial distance from the lower end of the bit I2 or I2 when inthe operative position at the bit. The instrument 6| is fixed to the go-devil 58 and when the go-devil' comes to rest on the seat 55 the surveying instrument 6| is in a given or non-rotative posi tion with respect to the bit I2 or I2 and the string S. Accordingly, the record produced by .the instrument 6I accurately-indicates both the rotative position and the angularity of the bit 7 I2 or I2 7 1 In operating the apparatus and in carrying out the method of the invention it is usually desirable to determine the direction and the angularity of the intended side track bore or directional bore D. With these factors in mind the section II is formed to have the desired or required curvature or angularity. The equipment is assembled as illustrated in the drawings with the mechanism or impact generator I0 .se-

cured to the lower end of the section I I and provided with a selected form of bit I2 or IZ It is to be understood that the section I I is shaped, bent or made angular prior to running the equipment into the well. The string S is assembled and run into the well in the usual manner until the bit 12 or I2 assumes a position adjacent the bottom of the well bore B. .Owing to the curvature or angularity of the section II the bit I2 or I2 will assume a position adjacent the wall of the bore B and the string S or the upper part of the section II will assume a position adjacent the well wall opposite and above 'the instrument (H is run into the string S on the line L. Thego-devil is lowered until its face 60; cooperates with the seat 56. As above described,

this cooperation automatically brings the sur-' veying instrument 6| to a given and known rotative position with respect to the bit I2 or I2 and the string S; The surveying instrument GI" is operated or permitted. to operate to produce its record and is then withdrawn from the well. Examination of the record produced by thesurveying instrument 6I reveals'the position of is proportioned to pass the bit H2 or l2 in the well bore B. In most cases it will be found that the bit is not in the correct rotative position to begin the directional drilling operations and it is necessary to bring the bit to the correct position. This is done by merely turning the string S to re-locate the bit. The bit l2 or l2 may be suspended from the bottom of the well bore B or may rest lightly on the well bottom so that it may be freely turned to its new position. When the string S is suspended from the top of the well to hold the bit i2 free the clutch parts 26 are engaged and the bit may be readily turned to the new position with the assurance that it will be correctly located. Following these operations it may be desired to determine if the bit I2 or I2 has been moved to the correct position. This may be done by running the go-devil 58 and surveying instrument 6! down through the string S to again engage the go-devil on the seat 56. The surveyinginstrument iii takes another reading or makes another record and when the line L is withdrawn this record may be examined to determine if the bit if is in the correct position. In this way the directional drilling bit may be accuratelyoriented.

Following the locating or orienting of the bit [2 the string S is lowered to engage the bit against the earth formation and the string is then reciprocated to operate the mechanism or impact generator it The imp-act mechanism or generator lEl operates as described'above to impart heavy downward blows or impacts to the section II and bit I2. The bit 12 or 12 is operated by these impacts and cuts away the earth formation to form the directional bore D. It is important to note that the bit is. operated to form the directional bore D without rotating the operating string S and therefore without altering the position of the orienting bit. The directional drilling bit i2 forms a directional bore D whose position or direction has been accurately determined by the 'abot e described orienting operations and whose angularity has been determined by giving the section II the intended or required curvature or angularity. The directional bore D may be drilled to the required depth by means of the directional drilling equipment and circulation fluid may be pumped down through the string to discharge at the bit during these drilling operations. When the directional bore D has been drilled to a suitable depth the equipment is withdrawn from the well and regularrotary drilling operations may be resumed to continue the directional lar string section, an impact bit and means for operating the bit comprising an element on the bit, an element on said section, one element being a tubular body, the other a tubular mandrel shiftably and telescopically related to the body, a hammer mechanism in the body operable by telescopic movement of the elements to impact downward blows to the bit, and means for maintaining a lubricant bath in the body.

2. Well drilling apparatus for use on a tubular well drilling string comprising a curved tubular string section, an impactbit, and means for operating the bit comprising an element on the bit, an element on said section, one element being a tubular body, the other a tubular mandrel shiftably and telescopically related to the body, a hammer mechanism in the body operable by telescopicmovement of the elements to impart downward blows to the bit, thebody being adapted to contain a lubricant bath, and means for keeping the bath out of communication with the fluid in the string comprising a barrel communicating with the string and body, and a floating follower in the barrel.

3. Well drilling apparatus for use on a tubular well drilling string comprising a curved tubular string section, an impact bit, and means for operating the bit comprising an element on the bit, an element on said section, one element being a tubular body, the other a tubular mandrel shiftably and telescopically related to the body, a hammer mechanism in the body operable by telescopic movement of the elements to impart downward blows to the bit, the body being adapted to contain a lubricant bath, and means for keeping the bath out of communication with the fluid in the string comprising a barrel communicating with the string and body, a floating follower in the barrel separating the bath and said fluid, and packing means on the follower slidably sealing with the internal surface of the barrel..

ARTHUR L. ARMENTROUT. 

